Automatic gain control or AGC systems are known and widely used. However present communications systems being developed and proposed, such as UMTS (Universal Mobile Telephone Systems) also known as WCDMA (Wideband Code Division Multiple Access) when referring to the air interface, are considering relatively high data rates with complex modulation schemes and channel coding schemes each of which is expected to place very stringent demands on the overall AGC system that is used for receivers that will be deployed in these systems. Current AGC systems have suffered from one or more problems such as limited control range, limited accuracy, slow acquisition times, or discontinuous gain control characteristics any or all of which can be a serious problem for a WCDMA receiver.
Thus, what is needed is an apparatus and corresponding methods of automatic gain control that do not suffer from these problems and that will be compatible with new receivers for systems such as UMTS or WCDMA.